Dental plugger.



No. 629,62I. Patented luly 25, i899. G. B. SNOW.

DENTAL PLUGGER.

(Application tiled May 12,'1899,)

(No Model.)

UNITED STATES `PATENT O EincE- GEORGE B. SNOV, OF BUFFALO, NEV YORK.

DENTAL PLUGGER.

SPECIFICATION forming part of Letters Patent No. 629,621, dated July 25,1899.

Application filed May l2, 1899.

My invention relates to dental pluggers,the

same being particularly designed as an improvement upon the pluggershown and de-v scribed in reissued Letters Patent No. 9,248, grantedtome June 8, 1880.

The object of the invention is 'to provide means for adjusting thetension of the hammer-impelling spring and for indicating the degree ofadjustment of the same, for regulating the length of stroke of thetool-holder.

and for indicating the degree of regulation thereof, and for controllingthe character of blow imparted by the hammer upon the toolholder so asto produce a soft or cushion blow or a hard or unyielding blow or onewhich is at first soft or yielding and afterward hard or unyielding.

The construction of parts by which the.

above objects are attained will be fully set forth hereinafter, and thenovel features of.

the invention will be defined in the claims.

In the drawings forming part of this specitication, Figure 1 is a sideelevation of my improved plugger. Fig. 2 is a longitudinal section ofthe same. Fig. Slis a perspective view of the lower section of thecasing. Fig. 4- is a similar view of the detent, and Fig. 5 is asectional view of a modified form of hammer. Fig. 6 is a detailsectional view showing a modified construction of the upper end ofcasing, cap, yand jam-nut cooperating therewith.

Like reference-numerals indicate like parts in the different views.

The casing of myinstrument is made up of an upper tubular section 1 anda lower section 2, adaptedto be screwed in the lower end thereof. On theinside of the section 1, adjacent to its lower vend,-is a spline orfeather 3, and on the inside of said section, adjacent to the upper endthereof,but opposite the feather 3, is a releasing-dog 4, havingadownwardlyextending projection 5 thereon, which is beveled along itsouter surface. Fitting within the section 1 of the casing and restingnor- Serial No. 716,573. (No model.) 1

mally upon the end of the spline 3 is the hammer 6, which is providedwith a longitudinal groove 7 and with a transverse recess 8,intersecting the groove 7, and provided with a selries of notches or teeth 9.The upper end of said hammer is formed with a stem or cylindricalextension 10, which is surrounded by -the lower end of a coiled spring11, whose npyper end abuts against the inner side of a cap 12, asclearly shown in Fig. 2 of the drawings. The said cap 12 is providedwith a milled or knurled finger-engaging portion-13 and is internallythreaded,as shown at 14. The threads 14 are adapted to mesh withcorresponding external threads 15 on the upper end of the section 1. 1is provided with circumferential scores 16 16, which are arranged inparallel relation and at equal distances from each other. Fittinguponthe section 1 and engaging the threads l5 thereof isa jam-nut 17,provided with a milled finger-engaging portion 18 and with aforwardly-extending-sleeve ortubular portion 19, which is adapted tocover up and conceal the threads 15 below the lower end of the cap 12.The force of the blow of the hammer 6, which is imparted by the spring11, may be controlled by screwing inwardly or outwardly the cap 12, andsaid cap may be locked in its adj usted position by means of the jam-nut17. The degree of adjustment of the cap 12 with respect to the section 1may also be determined by the scores 16 on the section 1-that is to say,if the outer or upper score of the series is opposite the lower edge ofthe sleeve or tubular .portion of the jam-nut 17 it will be apparentthat the spring 11 is not tightlycompressed, whereas if the inner orlower score 16 of the series is opposite the lower edge of the sleeve ortubular portion of the jam-nut it will be apparent that the spring isvery much compressed, and consequently the force of the blow imparted tothe hammer 6 by said spring will be great. Intermediate tensions will beindicated by the adjustment of one of the intermediate scores oppositethe lower edge of the jam-nut.

It will be understood,'of course, that the spline or feather 3 limitsthe downward movement of the hammer 6 and that the longitudinal groove 7in said hammer embraces the Below the threads 15 the section IOOreleasing-dog 4, so that rotary movement of said hammer is prevented bysaid dog.

The lower section 2 of the Casin g carries the outwardly spring-pressedtool-holder 20, and said tool-holder has secured to its upper end thedisk 21, provided with two notches 22 23,1ocated at diametricall yopposite points, the notch 22 serving to permit of the upward movementof the disk 21 on the spline or feather 3 and to prevent the rotation ofthe tool-holder, and the notch 23 serving as a means of connection forthe spring-actuated detent 24. Said detent is made up of a fiat strip ofmetal having oppositely-disposed notches 25 25 adjacent to its lowerend, which form ya web 26,that is received in the notch 23 of the disk2l, heretofore referred to. The upper end of said strip is beveled, asshown at 27, and on its inner surface, adjacent to its beveled upperend, said stripis formed with a tooth 28, which is adapted to fit withinor engage one or the other of the series of notches or teeth 9 in thehammer 6. The said strip is normally held inwardly so as to engage saidnotches by means of the'spring 29, which is secured at its lowerl end tosaid strip and is adapted-to engage the inner surface of the section lof the casing.

The upper end of the section 2 is formed with external screw-threads 30,which mesh with correspondinginternal screw-threads in the lower end ofthe section l. By this means the two sections may be secured one to theother and the degree of penetration of the section 2 into the section lmay be regulated. This regulation is for the purpose of varying thelength of stroke of the tool-holder 20, the

said regulation causing the tooth 28 on the detent 24 to engage one orthe other of the series of notches 9 in the hammer 6. In the drawings Ihave shown three of said notches 9, which will serve to illustrate theinvention; but of course I do not care to be limited to this exactnumber. The section 2 is adapted to be locked in its adjusted positionon the section l by means of a jam-nut 31, which is internallyscrew-threaded, is formed with a milled finger-engaging portion, isadapted to engage or abut against the lower end of the section l, and isformed with a downwardly or outwardly extending sleeve or tubularportion 32. Coperating with said jam-nut or the tubular portion 32thereof is a series of scores 33 upon the outer surface of the section2, spaced the same distance apart as the notches 9, by means of which itmay be determined from the outside which one of the notches 9 the tooth28 on the detent 24 is in engagement with.

In the foregoing description I have set forth the means for adjustingthe tension 0f the hammer-impelling spring and the means for regulatingthe length of stroke of the `toolholder, as well as the generalconstruction of the device and its method of operation. It is sometimesdesirable, however, that a soft or cushion blow be imparted bythehammcr.

In order to provide means whereby this may be effected, I form in thehammer 6 a central longitudinal bore or opening 34, which extendsthrough the stem lO and is formed with an internal annular shoulder 35at its lower end. Fitting within the bore or opening 34 is astriking-piece 36, which has an annular shoulder 37 thereon engaging theinternal shoulder 35 in the bore 34 and normally lying Hush with thelower end of the body p0rtion 6 of said hammer. Behind the strikingpiece36 and fitting within the bore 34 is a coiled spring 3S, which is actedupon at its rear or upper end by a screw-plug 39, which lits within andengages internal screw-threads in the bore 34T. It will of course beapparent that by screwing the plug 39 inwardly toward the striking-piece36 the spring 38 may be compressed to any desired degree and the tensionof said spring upon the striking-piece 36 controlled. As the hammer isactuated by the means heretofore described the strikingpiece 36 will bebrought in contact with the upper end of the tool-holder 20 and a softor cushion blow imparted thereto, and the degree of cushioning effect ofsaid blow may be readily controlled.

I have also illustrated in the drawings another form of hammer, which issimilar to that just described except that the stern l0 is dispensedwith and the screw-plug 39 has formed upon its lower or inner end a pinor projection 40, which is adapted to fit down within the spring 38, asshown. I have also pro vided a jam-nut 4l, by means of which the plug 39may be locked in its adjusted position on the hammer 6. In this form ofhammer it will be observed that I can adjust the plug 39l down into thebody of the hammer 6 until the pin 40 is brought in Contact with theupper end of the striking-piece 36, at which time a hard or unyieldingblow will be imparted by the ham mer to the tool-holder 20. Byunscrewing the plug 39 slightly the pin 40 can be removed from the upperend of the striking-piece 36, and then a blow will be imparted by thehammer, which will be at first soft, but afterward, when thestrikingpiece 36 comes in contact with thelower end of the pin 40, willbe hard and unyielding. By further unscrewing the plug 39 from the bodyof the hammer 6 the pin 40 can be so far removed from the striking-piece36 that the blow imparted by the hammer will be soft or yieldingthroughout, it being understood, of course, that the downward movementof the hammer 6 will be limited by its engagement with the spline orfeather 3.

The operation of my device is as follows: With the parts in the positionthey are shown in in Fig. l the tool in the tool-holder 2O is applied tothe filling of the tooth and forced against it. This action causes thetool-holder 2O to be forced inwardly into the section 1 of the casing,or, more properly speaking, the section l ofthe casing is forced downupon the tool-holder 20. In any event, how- ICO IIO

ever, relative longitudinal movement between said tool -holder and saidcasing is brought about. This action, by reason of the engagement of thetooth 28 of the detent 24 with one of the notches 9 in the hammer o,forces said hammer upwardly against the action of its spring ll. Assoon, however, as the beveled end 27 of the detent 24 is brought intocontact with the beveled projection of the releasing-dog 4 said detent24 is retracted against the action of its spring 29, and the tooth 28 isdisconnectedl from the notch 9 of the hammer 6. The said hammer is t-henimpelled by the influence of its spring ll against the end of thetoolholder .20 and imparts a blow t-o the tool. As the tool-holder isnormally downwardly or outwardly springpressed, and as the downwardmovement of the hammer o is limited by the spline or feather 3, as soonas the blow has been struck the parts return to their normal position,and the instrument is ready for further action in a manner similar tothat above described. If it be desired to lengthen the stroke of thetool-holder 20, it is merely necessary vto unl screw the section 2 fromthe section l to such an extent that the tooth 28 on the detent 24 willbe in proper position to engage the lower notch 9 on the hammer 6. Theproper degree of movement to effect this adjustment may be determined bythe scores 33 on the section .2.-that is, for the longest stroke thejam-nut 3l will be so adjusted with respect to the section 2 that theouter edge of the sleeve portion 32 of said nut will register with theinner'or upper score of the series. To shorten the stroke, a reverseoperation to that just described would be performed, it being understoodthat the number of scores 33 will correspond with the number of notches9 and will be so located on the section 2 that the proper adj ustmentmay be readily determined from the outside of the instrument. Theadjustment of the tension of the spring 1l may be effected in a similarmanner, and the character of the blow imparted by the hammer 6 may beregulated, as hereinbefore set forth.

` NVhile theconstruction described for ad justing and locking the parts-12 and'2 upon the tubular section l and the relative arrangement of thejam-nuts and scores are deemed by me to be preferable at this time, itwill of course be understood that Ido not limit myself tothe exactdisposition and arrangement of parts shown, but reserve the right tochange, vary, or otherwise modify the same within the terms of theclaims. For example, in Fig. 6 of the drawings I have shown the casingprovided with vinternal screw-threads 2 and the cap with externalscrew-threads 43, meshing therewith, which is a mere reversal of theconstruction shown in Fig. 2. In this form of the invention also thejam-nut 44 engages the screw-threads Qn the cap instead of on the casingand cooper# ates with scores 45 on said cap. The operation is similar tothat of the former construction..l Furthermore, I do not desire to limitmyself to the use of the novel features of my invention upon the exactform of denial-plugger herein shown and described, as it is evident thatthis may be varied at will without departing fromvthe spirit of myinvention.

Having thus described my invention, what Iclaim isi l. In a dentalplugger, a casing, a tool-actuating hammer and an impelling-spring forthe hammer, in combination with a cap provided with screw-threadsmeshing with corresponding threads on said casing, and a sleeved jam-nutacting upon said'cap 'and casing for locking the cap in adjusted posi-`cap in adjusted position and to cooperate with said scores forindicating the degree of ad.- justment of said cap. l

3. In a dental plugger, a casing having two sections adjustablelongitudinally with respect to each other,.one provided with a series ofscores, a spring-actuated hammer in one o'f said sections,atool-holderin the other of said sections adapted to have its length ofstroke regulated by the relative adjustment of said sections, and ajam-nut for locking said sections in adjusted position and adapted tocooperate with said scores for indicating the degree of adjustment ofsaid sections.

4.- In a dental plugger, a casing having two sections adjustablelongitudinally with respect to each other, one of said sections providedwith a series of scores, a hammer and an impelling-spring therefor inone of'said sections, said hammer being provided with a plurality ofengaging portions, `a tool-holder in the other of said sections, adetent connected to the tool-holder and adapted to engage one or theother of the engaging portions on said hammer, and a jam-nut for lockingthe two sections of the casing in adj usted position, said jam-nutadapted to cooperate withy said scores for indicating the degree `ofadjustment of said sections.

5. In adental pl ugger, a reciprocating hammer having a yieldingreciprocating striking piece thereon. v

6. In a dental plu gger, a reciprocating hammer, and reciprocating meanswhereby a sof t or cushion blow may be imparted thereby.

7. In a dental plugger, a reciprocating hammer, means whereby a soft orcushion blow may be imparted thereby, and means for regulating thedegree of softness or cushioning effect thereof.

8. In a dental plugger, a hammer, means whereby a soft or cushion blowmay he im- IIO i i l 629,621

parted thereby, means for regulating the degree of softness orcushioning effect thereof, and means whereby a hard or unyield ing blowmay be imparted thereby.

9. In aden tal plugger,a ham 1ner,and means whereby a blow may be imparted thereby Vwhich is at first soft or yielding and afterward hardand unyielding.

10. In a dental plngger, a hammer, an ndependenily-movablestriking-piece thereon, and a spring acting upon said striking-piece, asand for the purpose set forth.

11. In a dental plugger, a hammer, an independently-movablestrikingpieee thereon, a spring acting upon said striking-piece, andmeans for adjusting the tension of said spring, as and for the purposeset forth.

12. In a dental plugger,v a hammer having a longitudinal bore therein, astriking-piece at one end of said bore, a screw-plug at the opposite endofsaid bore, anda spring interposed between said striking-piece and saidplug.

13. In a dental pl ugger, a hammer having a longitudinal bore thereinprovided with a shoulder near one end and screw-threads at its oppositeend, a striking-piece in said bore having its movement in one directionlimited by said shoulder, a threaded plug engaging the threads in saidbore, and a spring interposed between said strikingpieee and said plug,as and for the purpose set forth.

` 14. In a dental plugger, a hammer having a longitudinal bore therein,a striking-piece at one end of said bore, a oeil-spring behind saidstriking-piece, and a screw-plug in the end of said bore opposite saidstriking-piece, adapted to oom press said spring and provided with a pinextending through said spring and adapted to engage the rear end of saidstrik ingpieee, as and for the purpose set forth.

In testimony whereof I have hereunto set my hand in presence of twosubscribing Witnesses.

GEORGE B. SNOV.

XVitnesses:

CHARLEs E. CLARK, EDWARD G. AIDOLFF.

